Answer:
D. 12 cm
Explanation:
A node is a point on a standing wave that does not vibrate.
The nodes of a standing wave are shown in the following sketch.
The red dots are the nodes of the standing wave.
It is observed that the distance between two adjacent nodes is half the wavelength of the wave.
Therefore, if the wavelength of the wave is 24 cm, then the distance from one node to the net must be 24 / 2 = 12 cm.
Hence, choice D is the correct answer.
